I have no meter other than the bars on the ht and a good multimeter.
Is this on track?
I split the driven and leave how much room between the two pieces?
Will 10 gauge wire make a big difference between from the below specs?
70 Centimeter 4 element beam center frequency 440 MHz

70 Centimeter 4 element beam
1/8" diameter tubing
Element Length
Element spacing
from Reflector

Reflector
13"
*****

Driven
12"
8-1/16"

Director 1
11-7/8"
16-3/4"

Director 2
11-3/4"
23-3/8"











"Ralph Mowery" wrote in message ink.net...

"Moto579" wrote in message
...
I would like to build a yagi for 448 mhz rangr for home use I have a 12
foot
1x1" piece of cedar and some 10 gauge copper wire It measures 0.15625" I
think it is 10 gauge. Am I wasting my time? Also how do I use 75 ohm
line
as a feed line? All the plans I have found are for 50 ohm feedlines. It
is
all I have for wire and living out in the boonies it is difficult to
travel
to pick up some 50 ohm.

Don't worry about the 50 or 75 ohm feedline. Just build the antenna and
feed it with what you have. If you build an antenna with a matching section
and have a good swr meter calibrated to 75 ohms you can match it.
If you don't have a meter you will have to take whatever you get.

Using #10 wire instead of 1/8 tubing will very slightly raise the
frequiency, not enough to worry about. If you mount it for vertical
polarization, at least the top 2 feet of the mast should be non metallic,
wood or plastic water pipe. How are you going to match the feedline to the
driven element? I hope the 4 element beam has instructions for that.

Tam/WB2TT


"Moto579" wrote in message
...
I have no meter other than the bars on the ht and a good multimeter.
Is this on track?
I split the driven and leave how much room between the two pieces?
Will 10 gauge wire make a big difference between from the below specs?
70 Centimeter 4 element beam center frequency 440 MHz
70 Centimeter 4 element beam
1/8" diameter tubing Element Length Element spacing
from Reflector
Reflector 13" *****
Driven 12" 8-1/16"
Director 1 11-7/8" 16-3/4"
Director 2 11-3/4" 23-3/8"










"Ralph Mowery" wrote in message
ink.net...

"Moto579" wrote in message
...
I would like to build a yagi for 448 mhz rangr for home use I have a 12
foot
1x1" piece of cedar and some 10 gauge copper wire It measures 0.15625" I
think it is 10 gauge. Am I wasting my time? Also how do I use 75 ohm
line
as a feed line? All the plans I have found are for 50 ohm feedlines. It
is
all I have for wire and living out in the boonies it is difficult to
travel
to pick up some 50 ohm.

Don't worry about the 50 or 75 ohm feedline. Just build the antenna and
feed it with what you have. If you build an antenna with a matching
section
and have a good swr meter calibrated to 75 ohms you can match it.
If you don't have a meter you will have to take whatever you get.